Apparatus and method for detecting pe open of electric vehicle charging controller

Abstract

An apparatus for detecting protective earth (PE) open of an electric vehicle charging controller (EVCC) according to one embodiment of the present invention comprises: a first voltage detection unit for detecting a negative voltage of a connector proximity detection line; and a control unit for determining that a PE between electric vehicle supply equipment (EVSE) and the electric vehicle charging controller is open when the voltage value detected by the first voltage detection unit is within a predetermined value.

Description

Device and method for detecting open PE of electric vehicle charging controller

[0001] The present invention relates to an electric vehicle, and more particularly, to a PE open detection device and method of an electric vehicle charging controller.

[0002] Eco-friendly vehicles such as electric vehicles (EVs) or plug-in hybrid electric vehicles (PHEVs) use electric vehicle supply equipment (EVSE) installed at charging stations to charge their batteries.

[0003] To charge an electric vehicle, the EV and EVSE communicate via a charging connector. Once the charging connector is connected, charging begins after signaling is performed between the EVSE and EV.

[0004] Meanwhile, high voltage current flows between the EVSE and the EV, and when an emergency shutdown is required, a stopping message corresponding to the shutdown reason can be transmitted from the EV to the EVSE.

[0005] If the PE (Protective Earth) line, the grounding wire between the EVSE and the EV, is open, an emergency shutdown is required for safety reasons. Therefore, technology is needed to quickly and accurately detect PE open circuits.

[0006] The technical problem to be achieved by the present invention is to provide a device and method for quickly and accurately detecting the opening of a protective earth (PE) of an electric vehicle charging controller.

[0007] A PE (protective earth) open detection device of an electric vehicle charging controller (EVCC) according to one embodiment of the present invention includes a first voltage detection unit that detects a negative voltage of a connector proximity detection line, and a control unit that determines that the PE between an EVSE (Electric Vehicle Supply Equipment) and the electric vehicle charging controller is open when the voltage value detected by the first voltage detection unit is within a predetermined value.

[0008] The above control unit can estimate the negative voltage of the voltage value detected by the first voltage detection unit using a pre-stored voltage matching table.

[0009] The first voltage detection unit includes a back-to-back FET (back to back field effect transistor), a positive voltage monitoring circuit, and a negative voltage monitoring circuit connected to the connector proximity detection line, and the negative voltage monitoring circuit may include a voltage distribution resistor and an OP Amp (operational amplifier).

[0010] The voltage distribution resistor unit includes a first resistor and a second resistor, one end of the first resistor is connected to the connector proximity detection line, and the other end of the first resistor can be connected to one end of the second resistor and the OP Amp.

[0011] The above first resistance may be 100 kΩ or more.

[0012] The above positive voltage monitoring circuit may include a voltage distribution resistor and an operational amplifier (OP Amp).

[0013] It may further include a second voltage detection unit that detects the voltage of the charge status detection line.

[0014] The second voltage detection unit may include a voltage distribution resistor and an operational amplifier (OP Amp).

[0015] The voltage distribution resistor unit includes a first resistor and a second resistor, one end of the first resistor is connected to the charge status detection line, and the other end of the first resistor can be connected to one end of the second resistor and the OP Amp.

[0016] The above first resistance may be 100 kΩ or more.

[0017] A method for detecting an open PE (protective earth) of an electric vehicle charging controller (EVCC) according to one embodiment of the present invention includes a step of detecting a negative voltage of a connector proximity detection line, and a step of determining that the PE between an electric vehicle supply equipment (EVSE) and the electric vehicle charging controller is open when the voltage value detected in the detecting step is within a predetermined value.

[0018] According to an embodiment of the present invention, an electric vehicle charging controller that quickly and accurately detects the opening of a protective earth (PE) between an EVSE and an EV can be provided.

[0019] Figures 1 to 3 are drawings showing a charging system for an electric vehicle according to one embodiment of the present invention.

[0020] FIG. 4 is an example of a pinout of a connection part included in an EVCC according to an embodiment of the present invention.

[0021] Figure 5 is an equivalent circuit diagram of a charging interface between an EVSE and an EV.

[0022] FIG. 6 is an equivalent circuit diagram of a charging interface between an EVSE and an EVCC according to one embodiment of the present invention.

[0023] FIG. 7 shows an equivalent circuit diagram between a second voltage detection unit and an EVSE according to one embodiment of the present invention.

[0024] FIG. 8 shows an equivalent circuit diagram between a first voltage detection unit and an EVSE according to one embodiment of the present invention.

[0025] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0026] However, the technical idea of ​​the present invention is not limited to some of the embodiments described, but can be implemented in various different forms, and within the scope of the technical idea of ​​the present invention, one or more of the components between the embodiments can be selectively combined or substituted for use.

[0027] In addition, terms (including technical and scientific terms) used in the embodiments of the present invention may be interpreted as having a meaning that can be generally understood by a person of ordinary skill in the technical field to which the present invention belongs, unless explicitly and specifically defined and described, and terms that are commonly used, such as terms defined in a dictionary, may be interpreted in consideration of the contextual meaning of the relevant technology.

[0028] Additionally, the terms used in the embodiments of the present invention are intended to describe the embodiments and are not intended to limit the present invention.

[0029] In this specification, the singular may also include the plural unless specifically stated otherwise in the phrase, and when it is described as “A and / or at least one (or more) of B, C”, it may include one or more of all combinations that can be combined with A, B, C.

[0030] Additionally, in describing components of embodiments of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used.

[0031] These terms are intended only to distinguish one component from another, and are not intended to limit the nature, order, or sequence of the component.

[0032] And, when a component is described as being 'connected', 'coupled' or 'connected' to another component, it may include not only cases where the component is directly connected, coupled or connected to the other component, but also cases where the component is 'connected', 'coupled' or 'connected' by another component between the component and the other component.

[0033] Additionally, when described as being formed or arranged "above or below" each component, "above" or "below" includes not only cases where the two components are in direct contact with each other, but also cases where one or more other components are formed or arranged between the two components. Furthermore, when expressed as "above" or "below", it can include the meaning of a downward direction as well as an upward direction based on one component.

[0034] Hereinafter, embodiments will be described in detail with reference to the attached drawings. Regardless of the drawing numbers, identical or corresponding components are given the same reference numbers, and redundant descriptions thereof will be omitted.

[0035] FIGS. 1 to 3 are drawings showing a charging system for an electric vehicle according to one embodiment of the present invention.

[0036] Referring to FIGS. 1 to 3, an electric vehicle (EV) 10 can be charged from an electric vehicle supply equipment (EVSE) 20. For this purpose, a charging cable (22) connected to the EVSE (20) can be connected to an inlet of the EV (10). Here, the EVSE (20) is a device that supplies AC or DC, and can be placed at a charging station, placed at home, or implemented to be portable. The EVSE (20) can be used interchangeably with a charging station (supply), an AC charging station (AC supply), a DC charging station (DC supply), a socket-outlet, etc.

[0037] An electric vehicle charging controller (EVCC, 100) is mounted within an EV (10) and connected to the EV (10). For example, the EVCC (100) may be installed within the trunk of the EV (10), but is not limited thereto.

[0038] Here, EVCC (100) can communicate with EV (10) and EVSE (20), respectively.

[0039] According to an embodiment of the present invention, EVCC (100) includes a control unit (110), a connection unit (120), and a detection unit (130).

[0040] The control unit (110) generates a control signal for charging between the EV (10) and the EVSE (20). The control signal for charging generated by the control unit (110) can be transmitted to the EVSE (20) through the connection unit (120) or to the ECU (12) in the EV (10).

[0041] The connection unit (120) is connected to the EVSE (20) and transmits signals between the control unit (110) and the EVSE (20). For example, the connection unit (120) may transmit a charging-related signal received from the EVSE (20) to the control unit (110) and transmit a control signal for charging generated by the control unit (110) to the EVSE (20). In addition, the connection unit (120) transmits power received from the EVSE (20) to the battery (14) in the EV (10) according to the control signal for charging generated by the control unit (110).

[0042] The detection unit (130) detects a charging-related signal between the EV (10) and the EVSE (20). The detection unit (130) is connected to the connection unit (120) and the control unit (110), respectively, and can transmit a value detected from the connection unit (120) to the control unit (110).

[0043] Here, some components of the EVCC (100) may be used to detect a PE (protective earth) open. Accordingly, in the present specification, the EVCC (100) may be used interchangeably with a PE open detection device or a PE open detection device of an electric vehicle charging controller.

[0044] FIG. 4 is an example of a pinout of a connection part included in an EVCC according to an embodiment of the present invention. The pinout illustrated in FIG. 4 may be a shape shown at the end of an EV-side connector.

[0045] Referring to FIG. 4, the connector (120) may include a total of seven pins. For example, the connector (120) may include a DC+ pin, a DC- pin, a PE pin, a CC1 pin, a CC2 pin, an S+ pin, and an S- pin.

[0046] Here, the PE (protective earth) pin is a ground pin and can be a reference for the control line. The PE pin can be included in the grounding wire between the EVSE (20) and the EVCC (100). The CC1 (connection confirmation 1) pin and the CC2 (connection confirmation 2) pin are pins for confirming the connection between the EVSE (20) and the EV (10), respectively. The CC1 pin is a pin for distinguishing the charging status or charging mode, and the CC2 pin can be a pin for detecting connector proximity.

[0047] The DC+ pin and DC- pin may be rapid terminals that receive power from the EVSE (20).

[0048] The S+ pin and S- pin can be a CAN bus pin for signaling between the EVSE (20) and EV (10) sides.

[0049] These EV(10) side connectors may be Chaoji connectors called CHAdeMO 3.0 and may be compatible with CHAdeMO or GB / T DC charging systems.

[0050] Meanwhile, the end of the EVSE (20) side connector may also have a shape corresponding to the end of the EV (10) side connector.

[0051] As described above, the EVCC (100) can be mounted within the EV (10). Accordingly, in this specification, the EV (10) side may refer to the EVCC (100). That is, in this specification, the EVCC (100) may be used interchangeably with the EV (10) side.

[0052] Figure 5 is an equivalent circuit diagram of a charging interface between an EVSE and an EV.

[0053] Referring to Fig. 5, the CP (control pilot) circuit between the EVSE (20) and the EV (10) side includes power sources (U1, U2), switches (S1, S2, S2', Sv) and resistors (R1, R1', Rg, R4, R4', Rc, Rv). Switch S0 is an optional element and is always open to reduce the risk of a short between the power source (U1) and PE at the connector pins when the connector is not in use. Switch S3 and resistor R2 are optional elements to detect the integrity of the PE and CC1 lines on the EVSE (20) side before connecting the connector. The EVSE (20) and the EV (10) side can continuously monitor and evaluate the voltage values ​​at detection points (DP) 1 and 2 regardless of the charging preparation state or abnormal state. Detection point 3 can be monitored to detect a failure of the CC2 circuit on the EV (10) side due to the on-stuck of the switch Sv. In addition, the switch Sv is always open during charging to prevent the problem of double supply to the CP circuit due to the PE opening. At least one of the switches S1 and S2 can be opened in an emergency situation during charging. The resistors (R4', R4c, R4) and the switches (S2', S2) can be configured for compatibility between different charging standards. For example, if the equivalent circuit shown in Fig. 5 is an equivalent circuit according to the Chaoji standard, it can be compatible with a system according to a standard other than the Chaoji standard, such as the GB / T standard or the CHAdeMO standard, depending on the connection state of the switches (S2', S2).

[0054] Referring to the equivalent circuit of Fig. 5, the connection between the EVSE (20) and the EV (10) side is explained. The EV (10) side wakes up when the voltage at the detection point (DP) 2 is 12 V, and the switch Sv is turned on. Then, when the CC2 circuit is closed, the voltage at the detection point (DP) 3 is detected as 6 V. At this time, the EV (10) side can recognize that the connector is connected. The EVSE (20) can recognize that the connector is connected when the voltage at the detection point (DP) 1 decreases. Then, the EVSE (20) closes the switch S1 to prepare for charging. After that, CAN communication between the EVSE (20) and the EV (10) side starts.

[0055] Meanwhile, according to an embodiment of the present invention, the detection unit (130) detects a PE (protective earth) open between the EV (10) and the EVSE (20). Here, PE refers to a grounding wire between the EVCC (100) and the EVSE (20), and PE open refers to a state in which the grounding wire between the EVCC (100) and the EVSE (20) is disconnected. In this specification, PE open may also be referred to as a broken PE.

[0056] In the case where the grounding wire is disconnected at the charging interface between the EVSE (20) and the EVCC (100) as exemplified in Fig. 5, i.e., when a PE open occurs, the positive voltage values ​​at detection point 2 on the CC1 line and detection point 3 on the CC2 line may be different from the values ​​in the normal state. However, even in other fault states other than the case where a PE open occurs, the positive voltage values ​​at detection point 2 on the CC1 line and detection point 3 on the CC2 line may be different from the values ​​in the normal state. Accordingly, it may be difficult to quickly detect a PE open using only the positive voltage values ​​at detection point 2 on the CC1 line and detection point 3 on the CC2 line. Therefore, a faster and more accurate PE open detection method is required.

[0057] In an embodiment of the present invention, a circuit diagram of a charging interface between an EVSE and an EV is changed to implement a low-cost, fast, and accurate PE open detection structure.

[0058] FIG. 6 is an equivalent circuit diagram of a charging interface between an EVSE and an EVCC according to one embodiment of the present invention, FIG. 7 shows an equivalent circuit diagram between a second voltage detection unit and an EVSE according to one embodiment of the present invention, and FIG. 8 shows an equivalent circuit diagram between a first voltage detection unit and an EVSE according to one embodiment of the present invention.

[0059] Referring to FIGS. 6 to 8, the EVSE (20) and the EVCC (100) are connected by a CC1 (connection confirmation 1) line, a CC2 (connection confirmation 2) line, and a PE (protective earth) line. The CC1 line is a line for distinguishing a charging status or a charging mode, and the CC2 line may be a line for detecting connector proximity. Accordingly, the CC1 line may be referred to as a charging status detection line, and the CC2 line may be referred to as a connector proximity detection (PP) line. The PE line may be referred to as a grounding line. The EVCC (100) may recognize a charging status or a charging mode according to a voltage value of the CC1 line, and may detect proximity of the connector according to a voltage value of the CC2 line.

[0060] According to an embodiment of the present invention, the detection unit (130) of the EVCC (100) includes a first voltage detection unit (600) connected to the CC1 line to detect the voltage value of the CC1 line and a second voltage detection unit (610) connected to the CC2 line to detect the voltage value of the CC2 line. Here, the second voltage detection unit (610) may include a negative voltage monitoring circuit (612) that monitors the negative voltage of the CC2 line and a positive voltage monitoring circuit (614) that monitors the positive voltage of the CC2 line.

[0061] And, the control unit (120) of the EVCC (100) includes a CC1 MCU (600M) that generates a charging control signal using the detection value of the CC1 detection unit (600) and a CC2 MCU (610M) that generates a charging control signal using the detection value of the CC2 detection unit (610). The CC2 MCU (610M) may include a PE open MCU (612M) that generates a charging control signal for PE open using the detection value of the negative voltage monitoring circuit (612) of the second voltage detection unit (610) and a proximity signal MCU (614M) that generates a charging control signal for connector proximity using the detection value of the positive voltage monitoring circuit (614) of the second voltage detection unit (610). Although the CC1 MCU (600M), PE Open MCU (612M), and Proximity Signal MCU (614M) are illustrated as independent MCUs, this is not limiting, and the CC1 MCU (600M), PE Open MCU (612M), and Proximity Signal MCU (614M) may be implemented as a single integrated MCU.

[0062] The PE open MCU (612M) is connected to the negative voltage monitoring circuit (612), and when the voltage value detected by the negative voltage monitoring circuit (612) is within a predetermined value, it is determined that the PE (protective earth) between the EVSE (20) and the EVCC (100) is open.

[0063] To explain more specifically, when PE is open, a current flow occurs from the power source (U1) of the EVSE (20) through the CC1 line, the switch S2' of the EVCC (100), the switch S2, the CC2 line, the resistor Rc of the EVSE (20), and then back to the power source (U1) of the EVSE (20) due to the resistance component of the second voltage detection unit (610), and a negative voltage is applied to the CC2 line. Accordingly, in the embodiment of the present invention, the PE open is detected by using the negative voltage applied to the CC2 line.

[0064] According to an embodiment of the present invention, the second voltage detection unit (610) includes a negative voltage monitoring circuit (612), a positive voltage monitoring circuit (614), and a dual FET (616) connected to the CC2 line. Here, the dual FET (616) may include two FETs connected back to back. Accordingly, in the present specification, the dual FET (616) may also be referred to as a back to back FET. The back to back FET is arranged between the first node (N1) of the CC2 line and DC 12 V. The back to back FET is a system in which two FETs are connected in series with each other, but their body diodes are connected in opposite directions to block bidirectional current flow. When back-to-back FETs are placed between the first node (N1) of the CC2 line and DC 12 V, current flow through the CC2 line from the EVSE (20) toward the EVCC (100) is possible, but current flow through the CC2 line from the EVCC (100) toward the EVSE (20) is blocked. Accordingly, formation of a closed circuit between the CC1 line and the CC2 line can be prevented even when the PE is open.

[0065] According to an embodiment of the present invention, a negative voltage monitoring circuit (612) is connected to a first node (N1) of the CC2 line. The negative voltage monitoring circuit (612) may include a voltage-dividing resistor unit and an OP Amp (X1). Here, the voltage-dividing resistor unit may be disposed between the first node (N1) of the CC2 line and the OP Amp (X1) to distribute the voltage input to the OP Amp (X1). For example, the voltage-dividing resistor unit may include a first resistor (Ra) and a second resistor (Rb), one end of the first resistor (Ra) may be connected to the first node (N1) of the CC2 line, and the other end of the first resistor (Ra) may be connected to one end of the second resistor (Rb) and the OP Amp (X1). At this time, the first resistor (Ra) may be 100 kΩ or more, preferably 100 kΩ or more and 1000 kΩ or less, and more preferably 100 kΩ or more and 500 kΩ or less. In this way, if the first resistance (Ra) of the voltage distribution resistor is designed to be 100 kΩ or more, a structure capable of detecting an accurate voltage value without electrically affecting the surrounding circuit can be obtained.

[0066] According to an embodiment of the present invention, the negative voltage monitoring circuit (612) may further include a diode (D3) disposed between the voltage-dividing resistor and the OP Amp (X1). The cathode of the diode (D3) may be connected to the voltage-dividing resistor, and the anode may be connected to the OP Amp (X1). Accordingly, the flow of current from the OP Amp (X1) toward the voltage-dividing resistor is blocked, and the negative voltage of the CC2 line may be monitored.

[0067] Meanwhile, the PE open MCU (612M) is connected to the negative voltage monitoring circuit (612), and if the voltage value detected by the negative voltage monitoring circuit (612) is within a predetermined value, it determines that the PE (protective earth) between the EVSE (20) and the EVCC (100) is open. To this end, the PE open MCU (612M) may store in advance a voltage matching table for estimating the negative voltage using the voltage value detected by the negative voltage monitoring circuit (612). Table 1 is an example of a voltage matching table stored in advance by the PE open MCU (612M). For example, if the voltage value read by the PE open MCU (612M) is 0.05 V, the PE open MCU (612M) can estimate that the voltage value of the negative voltage of the CC2 line is -1 V, and if the voltage value read by the PE open MCU (612M) is 0.92 V, the PE open MCU (612M) can estimate that the voltage value of the CC2 line is -5 V, and if the voltage value read by the PE open MCU (612M) is 1.64 V, the PE open MCU (612M) can estimate that the voltage value of the CC2 line is -8 V. In addition, if the voltage value read by the PE open MCU (612M) is 0.68 V to 3.08 V, the PE open MCU (612M) can determine that a significant negative voltage is applied to the CC2 line and determine that the PE is in an open state.

[0068] CC2 Line Voltage Value (V) Detected Voltage Value (V) PE Open Detection Range 00-10.05-20.24-30.46-40.68 PE Open Detection -50.92-61.16-71.4-81.64-91.88-102.12-112.35-122.6-132.85-143.08-153.32-163.51

[0069] As in the embodiment of the present invention, when PE open is detected using a negative voltage applied to the CC2 line, fast and accurate PE open detection is possible.

[0070] Meanwhile, according to an embodiment of the present invention, the positive voltage monitoring circuit (614) may also include a voltage-dividing resistor unit and an OP Amp (X2). Here, the voltage-dividing resistor unit may be arranged between the first node (N1) of the CC2 line and the OP Amp (X2) to distribute the voltage entering the OP Amp (X2). For example, the voltage-dividing resistor unit may include a first resistor (Rh) and a second resistor (Rd), one end of the first resistor (Rc) may be connected to the first node (N1) of the CC2 line, and the other end of the first resistor (Rh) may be connected to one end of the second resistor (Rd) and the OP Amp (X2). At this time, the first resistor (Rh) may be 100 kΩ or more, preferably 100 kΩ or more and 1000 kΩ or less, and more preferably 100 kΩ or more and 500 kΩ or less. According to an embodiment of the present invention, if the positive voltage monitoring circuit (614) includes a voltage distribution resistor, the control unit (120) can also detect a high voltage value of 12 V or more and 16 V or less applied to the input line. In addition, if the voltage distribution resistor of the positive voltage monitoring circuit (614) includes a high first resistor (Rh) of 100 kΩ or more, the electrical influence of the positive voltage monitoring circuit (614) on the CC2 line can be minimized, and thus the accuracy of detecting a negative voltage of the CC2 line can be increased.

[0071] In this way, as illustrated in FIGS. 6 to 8, a negative voltage monitoring circuit (612), a positive voltage monitoring circuit (614), and a dual FET (616) may be connected to the first node (N1) of the CC2 line. Accordingly, in a normal state, a proximity detection signal is transmitted from the EVSE (20) toward the EVCC (100) through the dual FET (616), and the proximity detection signal can be detected by the positive voltage monitoring circuit (614). In addition, in a state where PE is open, a closed circuit between the CC1 line and the CC2 line is prevented by the dual FET (616), and a negative voltage applied to the CC2 line can be detected by the negative voltage monitoring circuit (612).

[0072] According to an embodiment of the present invention, the CC1 detection unit (600) detects the voltage value of the CC1 line. The CC1 MCU (600M) estimates the voltage value of the CC1 line using the result value of the CC1 detection unit (600), and can determine whether the EVCC (100) is in wake-up mode or sleep mode, or whether the EVSE (20) and the EVCC (100) are charging or not.

[0073] To this end, the CC1 detection unit (600) may include a voltage-dividing resistor unit and an OP Amp (X3). Here, the voltage-dividing resistor unit may be arranged between the second node (N2) of the CC1 line and the OP Amp (X3) to distribute the voltage entering the OP Amp (X3). For example, the voltage-dividing resistor unit may include a first resistor (Re) and a second resistor (Rf), one end of the first resistor (Re) may be connected to the second node (N2) of the CC1 line, and the other end of the first resistor (Re) may be connected to one end of the second resistor (Rf) and the OP Amp (X3). At this time, the first resistor (Re) may be 100 kΩ or more, preferably 100 kΩ or more and 1000 kΩ or less, and more preferably 100 kΩ or more and 500 kΩ or less.

[0074] If the CC1 detection unit (600) includes a voltage distribution resistor, when the EVSE (20) outputs a 12 V waveform, the CC1 detection unit (600) can obtain a result value lower than 12 V, for example, a result value of about 3 V, and the control unit (120) can estimate the voltage value of the CC1 line using the result value of the CC1 detection unit (600). In particular, if the first resistance of the voltage distribution resistor of the CC1 detection unit (600) is designed to be 100 kΩ or more, even if a voltage of 16 V is applied to the input line, the CC1 detection unit (600) can obtain a result value lower than 16 V, for example, a result value of about 4 V. In this way, if the CC1 detection unit (600) includes a voltage distribution resistor according to an embodiment of the present invention, the control unit (120) can also detect a high voltage value of the CC1 line, for example, a voltage value of 12 V or more and 16 V or less. In particular, if the voltage distribution resistor of the CC1 detection unit (600) according to an embodiment of the present invention includes a high first resistance of 100 kΩ or more, the electrical influence of the CC1 detection unit (600) on the CC2 line can be minimized, and thus the accuracy of negative voltage detection of the CC2 line can be increased.

[0075] Although the present invention has been described above with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below.

[0076] [Explanation of symbols]

[0077] 10: Electric cars

[0078] 20: Electric vehicle charging facilities

[0079] 22: Charging cable

[0080] 100: Electric Vehicle Charging Controller

[0081] 110: Control unit

[0082] 120: Connection

[0083] 130: Detection unit

Claims

1. In a PE (protective earth) open detection device of an electric vehicle charging controller (EVCC), A first voltage detection unit for detecting a negative voltage of a connector proximity detection line; A control unit that determines that the PE between the EVSE (Electric Vehicle Supply Equipment) and the electric vehicle charging controller is open when the voltage value detected by the first voltage detection unit is within a predetermined value. A PE open detection device comprising:

2. In paragraph 1, The above control unit is a PE open detection device that estimates the negative voltage of the voltage value detected by the first voltage detection unit using a pre-stored voltage matching table.

3. In paragraph 1, The first voltage detection unit includes a back-to-back FET (back to back field effect transistor), a positive voltage monitoring circuit, and a negative voltage monitoring circuit connected to the connector proximity detection line, The above negative voltage monitoring circuit is a PE open detection device including a voltage distribution resistor and an OP Amp (operational amplifier).

4. In paragraph 3, A PE open detection device in which the voltage distribution resistor includes a first resistor and a second resistor, one end of the first resistor is connected to the connector proximity detection line, and the other end of the first resistor is connected to one end of the second resistor and the OP Amp.

5. In paragraph 4, The above first resistance is a PE open detection device having a value of 100 kΩ or greater.

6. In paragraph 3, The above positive voltage monitoring circuit is a PE open detection device including a voltage distribution resistor and an OP Amp (operational amplifier).

7. In paragraph 1, A PE open detection device further comprising a second voltage detection unit for detecting the voltage of a charge status detection line.

8. In paragraph 7, The above second voltage detection unit is a PE open detection device including a voltage distribution resistor unit and an OP Amp (operational amplifier).

9. In paragraph 8, A PE open detection device in which the voltage distribution resistor section includes a first resistor and a second resistor, one end of the first resistor is connected to the charge state detection line, and the other end of the first resistor is connected to one end of the second resistor and the OP Amp.

10. In paragraph 9, The above first resistance is a PE open detection device having a value of 100 kΩ or greater.

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